Set of headphones



FIG. 1 is a perspective view of a set of headphones as seen from the front and left side;

FIG. 2 is a front view thereof;

FIG. 3 is a back view thereof;

FIG. 4 is a top view thereof;

FIG. 5 is a bottom view thereof;

FIG. 6 is a left side view thereof; and,

FIG. 7 is a right side view thereof.

The dotted line portions of the drawings represent environmental structure only and do not form part of the claimed design. 

CLAIM The ornamental design for set of headphones, substantially as shown and described. 